USN-4910-1: Linux kernel vulnerabilities

Published Apr 13, 2021
·
Updated

Ryota Shiga discovered that the sockopt BPF hooks in the Linux kernel could allow a user space program to probe for valid kernel addresses. A local attacker could use this to ease exploitation of another kernel vulnerability. (CVE-2021-20239) It was discovered that the BPF verifier in the Linux kernel did not properly handle signed add32 and sub integer overflows. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-20268) It was discovered that the priority inheritance futex implementation in the Linux kernel contained a race condition, leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-3347) It was discovered that the network block device (nbd) driver in the Linux kernel contained a use-after-free vulnerability during device setup. A local attacker with access to the nbd device could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-3348) 吴异 discovered that the NFS implementation in the Linux kernel did not properly prevent access outside of an NFS export that is a subdirectory of a file system. An attacker could possibly use this to bypass NFS access restrictions. (CVE-2021-3178)

Affected Software

68 affected componentsFixes available
All of the following
ubuntu/linux-image-5.8.0-1020-raspi<5.8.0-1020.23
5.8.0-1020.23
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-1020-raspi-nolpae<5.8.0-1020.23
5.8.0-1020.23
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-1023-kvm<5.8.0-1023.25
5.8.0-1023.25
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-1025-oracle<5.8.0-1025.26
5.8.0-1025.26
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-1027-azure<5.8.0-1027.29
5.8.0-1027.29
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-1027-gcp<5.8.0-1027.28
5.8.0-1027.28
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-1028-aws<5.8.0-1028.30
5.8.0-1028.30
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-49-generic<5.8.0-49.55
5.8.0-49.55
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-49-generic-64k<5.8.0-49.55
5.8.0-49.55
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-49-generic-lpae<5.8.0-49.55
5.8.0-49.55
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-49-lowlatency<5.8.0-49.55
5.8.0-49.55
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-aws<5.8.0.1028.30
5.8.0.1028.30
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-azure<5.8.0.1027.27
5.8.0.1027.27
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-gcp<5.8.0.1027.27
5.8.0.1027.27
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-generic<5.8.0.49.54
5.8.0.49.54
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-generic-64k<5.8.0.49.54
5.8.0.49.54
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-generic-lpae<5.8.0.49.54
5.8.0.49.54
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-gke<5.8.0.1027.27
5.8.0.1027.27
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-kvm<5.8.0.1023.25
5.8.0.1023.25
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-lowlatency<5.8.0.49.54
5.8.0.49.54
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-oem-20.04<5.8.0.49.54
5.8.0.49.54
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-oracle<5.8.0.1025.24
5.8.0.1025.24
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-raspi<5.8.0.1020.23
5.8.0.1020.23
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-raspi-nolpae<5.8.0.1020.23
5.8.0.1020.23
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-virtual<5.8.0.49.54
5.8.0.49.54
Ubuntu Ubuntu=20.10
All of the following
ubuntu/linux-image-5.8.0-49-generic<5.8.0-49.55~20.04.1
5.8.0-49.55~20.04.1
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-5.8.0-49-generic-64k<5.8.0-49.55~20.04.1
5.8.0-49.55~20.04.1
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-5.8.0-49-generic-lpae<5.8.0-49.55~20.04.1
5.8.0-49.55~20.04.1
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-5.8.0-49-lowlatency<5.8.0-49.55~20.04.1
5.8.0-49.55~20.04.1
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-generic-64k-hwe-20.04<5.8.0.49.55~20.04.33
5.8.0.49.55~20.04.33
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-generic-hwe-20.04<5.8.0.49.55~20.04.33
5.8.0.49.55~20.04.33
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-generic-lpae-hwe-20.04<5.8.0.49.55~20.04.33
5.8.0.49.55~20.04.33
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-lowlatency-hwe-20.04<5.8.0.49.55~20.04.33
5.8.0.49.55~20.04.33
Ubuntu Ubuntu=20.04
All of the following
ubuntu/linux-image-virtual-hwe-20.04<5.8.0.49.55~20.04.33
5.8.0.49.55~20.04.33
Ubuntu Ubuntu=20.04

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1020-raspi to a version that resolves this vulnerability.

    Fixed in 5.8.0-1020.23
  2. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1020-raspi-nolpae to a version that resolves this vulnerability.

    Fixed in 5.8.0-1020.23
  3. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1023-kvm to a version that resolves this vulnerability.

    Fixed in 5.8.0-1023.25
  4. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1025-oracle to a version that resolves this vulnerability.

    Fixed in 5.8.0-1025.26
  5. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1027-azure to a version that resolves this vulnerability.

    Fixed in 5.8.0-1027.29
  6. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1027-gcp to a version that resolves this vulnerability.

    Fixed in 5.8.0-1027.28
  7. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-1028-aws to a version that resolves this vulnerability.

    Fixed in 5.8.0-1028.30
  8. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-generic to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55
  9. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-generic-64k to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55
  10. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-generic-lpae to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55
  11. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-lowlatency to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55
  12. Upgrade

    Upgrade ubuntu/linux-image-aws to a version that resolves this vulnerability.

    Fixed in 5.8.0.1028.30
  13. Upgrade

    Upgrade ubuntu/linux-image-azure to a version that resolves this vulnerability.

    Fixed in 5.8.0.1027.27
  14. Upgrade

    Upgrade ubuntu/linux-image-gcp to a version that resolves this vulnerability.

    Fixed in 5.8.0.1027.27
  15. Upgrade

    Upgrade ubuntu/linux-image-generic to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.54
  16. Upgrade

    Upgrade ubuntu/linux-image-generic-64k to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.54
  17. Upgrade

    Upgrade ubuntu/linux-image-generic-lpae to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.54
  18. Upgrade

    Upgrade ubuntu/linux-image-gke to a version that resolves this vulnerability.

    Fixed in 5.8.0.1027.27
  19. Upgrade

    Upgrade ubuntu/linux-image-kvm to a version that resolves this vulnerability.

    Fixed in 5.8.0.1023.25
  20. Upgrade

    Upgrade ubuntu/linux-image-lowlatency to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.54
  21. Upgrade

    Upgrade ubuntu/linux-image-oem-20.04 to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.54
  22. Upgrade

    Upgrade ubuntu/linux-image-oracle to a version that resolves this vulnerability.

    Fixed in 5.8.0.1025.24
  23. Upgrade

    Upgrade ubuntu/linux-image-raspi to a version that resolves this vulnerability.

    Fixed in 5.8.0.1020.23
  24. Upgrade

    Upgrade ubuntu/linux-image-raspi-nolpae to a version that resolves this vulnerability.

    Fixed in 5.8.0.1020.23
  25. Upgrade

    Upgrade ubuntu/linux-image-virtual to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.54
  26. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-generic to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55~20.04.1
  27. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-generic-64k to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55~20.04.1
  28. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-generic-lpae to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55~20.04.1
  29. Upgrade

    Upgrade ubuntu/linux-image-5.8.0-49-lowlatency to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55~20.04.1
  30. Upgrade

    Upgrade ubuntu/linux-image-generic-64k-hwe-20.04 to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.55~20.04.33
  31. Upgrade

    Upgrade ubuntu/linux-image-generic-hwe-20.04 to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.55~20.04.33
  32. Upgrade

    Upgrade ubuntu/linux-image-generic-lpae-hwe-20.04 to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.55~20.04.33
  33. Upgrade

    Upgrade ubuntu/linux-image-lowlatency-hwe-20.04 to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.55~20.04.33
  34. Upgrade

    Upgrade ubuntu/linux-image-virtual-hwe-20.04 to a version that resolves this vulnerability.

    Fixed in 5.8.0.49.55~20.04.33

Event History

Apr 13, 2021
Advisory Published
via Ubuntu·12:00 AM
Data Sourced
via Ubuntu·12:00 AM
DescriptionAffected Software

Child vulnerabilities

Contains the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of USN-4910-1?

The severity of USN-4910-1 is considered high due to its potential exploitation of kernel vulnerabilities.

2

How do I fix USN-4910-1?

To fix USN-4910-1, upgrade your system to the latest available kernel version as recommended in the advisory.

3

Who is affected by USN-4910-1?

USN-4910-1 primarily affects users running Ubuntu 20.10 with specific versions of the Linux kernel.

4

What vulnerabilities are addressed in USN-4910-1?

USN-4910-1 addresses multiple vulnerabilities, including CVE-2021-20239, enhancing the kernel's security against local attacks.

5

Is it safe to continue using a system with USN-4910-1 vulnerabilities?

It is not safe to continue using a system with USN-4910-1 vulnerabilities, as it could facilitate the exploitation of further kernel vulnerabilities.

Company

Resources

Contact

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